KYIV, Ukraine — As Russia steps up its offensive in eastern Ukraine, weeks of failed attacks on a Ukrainian stronghold have left two Russian brigades in tatters, raised questions about Moscow’s military tactics and renewed doubts about its ability to maintain sustained, large-scale ground assaults.
The fighting has also come at a cost for Ukraine, which is expending vast amounts of ammunition to repel Russia’s growing numbers of ground troops, often supported by heavy armor, artillery and close air support. That has added urgency to Ukraine’s pleas for more ammunition, while Western allies this week expressed increasing concern about their ability to meet the demand.
The battle around the Ukrainian city of Vuhledar, which sits at the intersection of the eastern front in the Donetsk region and the southern front in the Zaporizhzhia region, is viewed as one of Moscow’s opening moves of a nascent spring offensive. Though it has been playing out for weeks, the scale of Russia’s losses is only beginning to come into focus.
Accounts from Ukrainian and Western officials, Ukrainian soldiers, captured Russian soldiers, Russian military bloggers, and video and satellite images all paint a picture of a faltering Russian campaign that continues to be plagued by dysfunction.
Moscow has rushed tens of thousands more troops, many of them inexperienced new recruits, to the front line in recent weeks as President Vladimir V. Putin’s forces seek to demonstrate progress before the anniversary of his full-scale invasion on Feb. 24.
Western officials estimate that the vast majority of Russia’s army is now fighting in Ukraine. Britain’s defense secretary, Ben Wallace, told the BBC on Wednesday that “97 percent of the Russian army” is in Ukraine. U.S. defense officials estimate that about 80 percent of Russia’s ground forces are dedicated to the war effort.
In attempting to capture Vuhledar, which lies near a rail line Russia uses to supply its forces, “the enemy suffered critical losses,” Col. Oleksii Dmytrashkivskyi, a spokesman for Ukrainian military forces in the area, said in an interview.
The Russians failed to take into account the terrain — open fields laden with mines — or the strength of the Ukrainian forces, he said. Two of Russia’s most elite brigades — the 155th and 40th Naval Infantry Brigades — were decimated in Vuhledar, Colonel Dmytrashkivskyi said.
In one week alone, the Ukrainian General Staff, which is responsible for military strategy, estimated that Russia lost at least 130 armored vehicles, including 36 tanks. That estimate has been supported by accounts from Russian military bloggers, whose reporting on the war is influential in Russia, and by drone footage of the destruction reviewed by independent military analysts.
Mr. Wallace on Wednesday cited reports that “a whole Russian brigade was effectively annihilated” in Vuhledar, where he said that Moscow “lost over 1,000 people in two days.” The British defense intelligence agency reported last week that Russian units had “likely suffered particularly heavy casualties around Vuhledar,” abandoning at least 30 armored vehicles after one failed assault.
Mr. Wallace told LBC News, a British news outlet, that the losses in Vuhledar showed the result of “a president and a Russian general staff that defies reality or ignores reality and simply doesn’t care how many people they are killing of their own, let alone of the people they are trying to oppress.”
Many of the captured soldiers were newly mobilized under a call-up Mr. Putin announced last September of some 300,000 recruits, while others had been recruited by the Wagner mercenary group, according to Ukrainian and Russian accounts.
In recent weeks, a rivalry between Wagner forces and the regular Russian army has opened up, with the mercenary group claiming that its fighters are more capable.
Natalia Yermakcontributed reporting.